Aqueous dispersions and methods of preparing the same



I. alcuu-zu nu5..aa, l-UUU AQUEOUS TDISPEHSIONS AND METHOD S OF PREPARING THE 'SAME' Mauricealnefiumeli, 'No'rotom Heights", Conng and William yanLoo, J r., Kym-N. Y -aassignorsetm Ameriean .-yanamid CcmpanyyNew yorleyNrY., a

a corporation of. Maine No Drawingif- Applicationne mbere; 2194s;

Serial No. 64;4518- consisting-:irofalnatural and regenerated r 0611111086821 and; mixtures: thereof The-present*inventionis an improvementmponw" the aqueous :dispersionsidisclosed andaiclaimediin i the copending application of Anne MacMillans Loukomslwm Roy? Kienle rand -.=Theodore --F.

Cooke; Serial:rNo'-.':64'-;4l6,= filed concurrently ;here.-' with; and includes the method ofipreparingrsuchi aqueous dispersions ,--involving thefimnroyementwhich consists in incorporating-into such:a dis.- persiomammoniumahydroxide in an-wamount cor-; responding to not less than-about' 14% 5 rby weightr'. of I the *dispersion; of ammonium hydroxide; .0011'! taining approximately :728% "NI-1 31 Thea-aqueous. dispersions": of=-;-sthe:--present-- in z vention comprise-=water: andeingredients come prising A5. y (1 i A 2 finely "divided; oxygenecontaining:irsub-e'r stancetofitheffigroup consisting Of ,EtiH,"ti-r 0 tanium; antimony and" bismuthmxides randmixtures thereof; l v (2) A :therm'oplastic "1 'substance containing rate least -20 by;aweight;of' -combinedahalogen and capable rof i-ruptu'ring under: heat ate carbonhalog'en;bondsz.

(3) A water- -soluble salt-of .an oxygen-contain ingacid of phosphorus-wherein .the pho'se'r 4 The ingredients of (1) i and (2) are employed a weight ratio of 1 part of the"formerto'ifoim' 0.6 t0-2O par-ts, moreparticularlyfromwx:to 4 1 parts, of the latter. The ingredients of (3) and (4) are employed iii-a weight ratio'lof l part of 1 the former; calculated as phosphoric acid. (I-IsPOl) to frcim- -l to 20'- pa'rts, more 'pairti'cu -li larl-y from 2 to --6 parts of thei'lattern -Thain gredients "of (A) and-:03) arer :presentaimztheo'55:

aqueousedispersion,rinsa' weightratio of l par-t Ofaithfi fOImeI tOefIOHI'POflrtO8 parts,-more par-eticu-larlyzzfromi-d to -3 partsy-of'the -latter;- The amount:v of: ammonium z hydroxide :which is pres- 5 -entacorrespondstoanot less-athansabout 4%,-m01er particularly ,from-1-r4%:to--about 9%, -.a'nd-;-prefuerably approximately 6 by weight ot-the'aque ous dispersion, of ammonium hydroxide con-v. taininge-sapproximately- 28% wNHsv The total amount z'ofr'water which is present in vthe aqueous-dispersion,- including that-which is present. inecombination: =withammonia in .13116 form x of ammonium ehydroxide is lfromlsabout 15% -:t0 abouts-35% ,-1 more particularly. from- 15 .to 125% and preferably approximately 220%; by. weight of v theaidlsDEISiOIl; v

Theeaqueous dispersions :offiour invention are. relativel 1;; stable aqueousv compositions; "De;- 1- pending upon +the. -amountwof-v water which. is I present therein andaotherinfluencing factors theyrmayvary:from-z-liquidsof varying --viscosities topasty masses on semi-solidsr-at room itemperae ture-t {about -95-? F.) the ilatter beingmcon- 1 verted' intoiree-flowing liquids when ,heatedatY an: elevated temperaturepe. g., at temperatures up-to about 2l60 -2F..- InlgeneraLithey are char acterized by their room-temperature stability againseseparationof -solids for a prolonged period, as evidenced by-the fact thatraqueous dis--- persionswf our -invention have=-'shown n0vsepa+- ratiomof-Ksolids iwhenallowed to remain undisturbed atrroom-temperature for periods ofmore than 1 week;- more rparticu'larlyc for periodsr rangingfwbetween i month and '1' yearn The-pH- v of; :oumdispersions, as." initially prepared; :usu-- allynis between about '6 or 6.5 ands or 8.5. The preferredwaqueous 'dispersi'ons also are dilutahle with-water to yield a dispersioncontaining-flapproximately '50% -by-w=weight--of solids, which" dil-ute dispersion: shows 'no separation. "of solids 1' upori standing undisturbed at: room tempera tllIGefOI-fi period oflataleast-24 hours, e. g.,.--for- 36-T=t0148' hOu1S'2alld 10ng81z j The aqueous :dispersions "of the present; invention-areradaptedr for use;-especially after- .di1u-' tion 1 with iwater innimparting: :flameresistancer-= to ia, cellulosicmaterial more-fparticularly a cel lulosicrmaiterial-ofthe class consisting of natural and regenerated ce11u1oses-:and mixtures there-- ofrbytmethods suchfas are more fullydes'cribed andr'are specificaliyclaimed inthe -aforemen-- tidned Lo1'1komsky" :etal. copending application"- with1particular-v reference P-to the aqueous r dis- 1 persionsa'hdis'closed and :.claime'd:in that; applica- 10m x i r v I. smears MUSSKULKLNUL I Sill-(UH U The present invention is based on our discovery that by incorporating ammonium hy droxide into aqueous dispersions of the kind described in the aforesaid Loukomsky et al. copending application, using a certain minimum quantity of ammonuim hydroxide and keeping the total amount of water within certain critical limits, it is possible to obtain an aqueous dispersion which is stable upon storage for a prolonged period at room temperature and which is dilutable with water as has been mentioned hereinbefore. This is a discovery of considerable practical importance and in no way could have been predicted from the known characteristics of ammonium hydroxide or from the characteristic properties of the aqueous dispersion described in the aforementioned Loukomsky et a1. application or from the properties of the ingredients used in the preparation of such a dispersion. The invention appears to be specific to the use of ammonium hydroxide, since aqueous solutions of other alkalies were tried, more particularly aqueous solutions of sodium hydroxide, potassium hydroxide and lithium hydroxide, but all were i'nefiective and .could not be used, as they resulted in the formation of insoluble reaction products in the dispersions.

The practical advantages of our discovery will be immediately apparent tothose skilled in the art. The stability of our dispersions, without sep aration of solid material or, otherwise stated,

without separation of clear liquid, for prolonged periods makes it unnecessary to use the disper-.,

sion shortly after its preparation. Hence it can be made and shipped wherever needed by a finisher of textile goods in the treatment of textiles to render them resistant to flame. Since it can preferably approximately 6%, by weight of the dispersion, of ammonium hydroxide containing approximately 28% NH3. It is not necessary to use only the concentrated form of ammonium hydroxide containing approximately 28% NHs,

or separation into two phases, would be objec= tionably affected.

One method of preparing our new aqueous dispersions comprises dissolving in water with the aid of heat, e. g., at a temperature between 140 F. and 210 ingredients comprising 1) a water-soluble salt of an oxygen-containing acid of phosphorus wherein the phosphorus atom has a valence of 5, e. g., a guanidine phosphate, a diguanidine Dy ophosphate, diammonium hydrogen phosphatefsodium polyphosphate, ammonium metaphosphate, the mono-, diand trial- "kylamine 'pyrophosphates, etc., and (2) a watersoluble nitrogenous substance of the group afore- "mentioned, the ingredients of (1) and (2) which are collectively designated as (B), being employed in weight ratios such as have been mentioned hereinbefore. The amount of water employed in dissolving the ingredients of (1) and (2) is such as will yield an approximately saturated solution, at a temperature of about 140 F. to about 160 F., of these ingredients. When the preferred ingredients, viz., monoguanidine phosphate and urea, are employed, a saturated solution can be produced by using such a relatively small amount of water that solids separate be prepared in the form of concentrated aqueous,

dispersions containinga relatively small amount of water, the user does not have to pay freight charges on a large amount of water. Instead, the textile finisher merely adds to the dispersion before using the same an amount of water,.

suflicient to bring the dispersionto the concentration of solids which he requires for his particular use.

The dispersions of ourinvention are prepared by incorporating ammonium hydroxide into the dispersion of the kind briefl described above and more fully in the aforementioned Loukomsky et a1. application at a suitable stage in the manvufacture of the dispersion, the amount of ammonium hydroxide employed corresponding to not less than about 4%, by weight of the final aqueous dispersion containing all of the ingredients, of ammonium hydroxide containing approximately 28% NI-Is. The amount of ammoniuni hydroxide specified above as the lower limit is the minimum required toobtain the desired results, as unsatisfactory results were obtained when ammonium hydroxide containing approximately 28% NI-Ia was used in an amount corresponding to 3% by weight of the dispersion. It does not appear that there is any critical upper limit to the amount of ammonium hydroxide employed from the standpoint of the amount of NH; introduced into the dispersion, but only in so far as the larger amounts of ammonium hydroxide may result in introducing an objection--.

ably large amountbf water into the dispersion. Ordinarily the amount of ammonium hydroxide introduced into the dispersion corresponds to from not less than 4% and not more than about 9%, more particularly from 5% to 7 or 8%, and

from the saturated solution when it is at a temperature of l60 F. Any solids that separate may be redissolved by heating the resulting saturated solution at a higher temperature of the order of 170 F. to 200 F. To the resulting solution is then added ammonium hydroxide in an amount corresponding to not less than about 4%, more particularly from 4 or 5 to 8 or 9%, 'by weight of the final aqueous dispersion con taining all of the ingredients, of ammonium hydroxicle containing approximately 28% NHa. This solution is preferably at an elevated temperature not higher than about 180 F. when the ammonium hydroxide is added thereto. Temperatures above 180 F. are not precluded but have theobjection that they create more of a hazard to the workman when adding the ammonium hydroxide thereto. Best results are usually obtained when the solution is at a temperature of the order of F. to 175 F., e. g., about F'., prior to the addition of the ammonium. A slight drop in the temperature of the solution generally results when the ammonium hydroxide isadded to the solution. The ammonium hydroxide may be heated, if desired, to avoid such a drop in temperature or the solution itself may befurther heated, after adding the NH4OH, to maintain the ingredients in solution.

To the resulting hot solution of the aforementioned water-soluble substances is added and dispersed therein an aqueous dispersion containing (3) a finely divided, oxygen-containing substance of the group consisting of tin, titanium, antimony and bismuth oxides and mixtures thereof and (4) a thermoplastic substance contaming at least 20% by weight of combined halogen and capable of rupturing under heat at carbon-halogen bonds. Examples of the thermoplastic substances of (4) that may be employed,

@iiGSS REFERENCE 2,5119% was less than 20%, advantageously not les-=than40%; by weight of combined chlorine or other halogen is present, forsinstanccs polyvinyl halides (e. g., polyvinyl chloride, polyvinyl bromide, etc.)

polyyinylidenewhalides (.e.-"g., g polyvinylidene .chloride polylvinylid neebromidel tcdwco eiymersl Ofufl: vinyl halideiandia yinylidener shall-idea (1e;- gue a lcopolymergofewinyllchloride; andavinylideneelo chloride. copolymers-l of a yinyL-;halide-;-, and-am acrylic-,iesterqfcrwinstancaia cop lymerzoftyinyi T chlorid elanda-nialkylgacsyl ate a g methyl, ;ethyl,,- propyl, butyl, etc., acrylates) halogenatedaten-gsa chlorinatedlgparaffins..eontainingpot less than .15 20% by weight of combined-halogen, more par= ticularlyhircmlabout.30.orA% 1 11.110 70 or 75% h by weight of combined chlorine, bromine pr other halogemwiThe ingredients of (3) and (4), which are collectively designated-t; as 1A), are tused:

weight ratios such as have been mentioned hereinbetore; and the ingredients .-of- -(A) and (B-)i likewise are employed in weightriatios Withre= spect to each other such as' previously have been giventwThe total i-amount of water used: in pres paring: the dispersion is controlled so that"th dispersion-containing allz of theing-redients present"threin'iiromf'about 151% jtoiabout -35% 7 more particularlyfront- 15 to 25' or and preferablyilfygapproximately :'20%,:? bytpweightk lot: :10 waters The finai step' in p-reparingthd dispe-rsion consists in vigorously agitating the ;hot dispersion, which initially "may be ata temperature of the crder'=of7150=F.TBQ IBGP F. for higherr while rapidly cooling-the: same" to "a temperature? of th'enrderbf SOQFJto "80or '90-F. ?*In",thisway=- theicrystals-f-of theixwater so-lnble=' phosphatemndr of the r,wateresolubleinitrogenous "substance are finely divided-,fand t'the; stability of thddisi ersion againsti'thei: separation",of soli'dsfis improved. stilhanothermethdd may-*beempioyed forpre paring-"the aqueous?dispersionsro-f our"inventions which dispersions likef'those't of the 'above-de scribed method, are"stable against the separa tion of solids for a prolonged period at room temperature: :1, Thisis methodm is essentially ;th'e sameeas-thati described :above with-,the. exception that thefinelyidividedi antimony oxide 501': other firi'elyw divided z-ioxygenwontainingc substancesis dispersed inrtthezwaterehaving dissolvedtherein the rwateresoluble-isalt:iofl the oxygengcontainingacid of phosphorus and themater-sol-uble 'nitro genous substance beiore-theammonium hydroxide is added theretoirand theraqueous dispersioni comprising the halogenated,thermoplastic sub-id stance is then added to the ammoniunrihydroxeidcmodi-fied dispers-ion-of--the-other ingredientsa- Whenz-cthe ainely -divided metallic oxide (or mixturewf metallicnqxidesn" is incorporated; into the dispersion. in combinatibnwith the 'halogen containing thermoplastic substancacthisimay be done, for instance, by first preparirvg a dispel sion ofvthe finiely divided metallicicxidelinavaiteni: with theuaid olf a suitable dispersing agent, e. g,

a sodium, potassium or otherealliali-metalrsalt' of a condensation product :of:formaldehyde'%an.d

a naphthalene sulfonic acid. This dispersion may be -passed through a colloid-milliinkorder' to reduce the particle sizeito,.for vexamp le,uone'- micron or .les's. then added a dispersion-of the halogen-containing thermoplastic. substance, more particularly a poly-vinyl:'halidepolyinerization product containing' atileast 40%"bycweight of combined halogen, and still vmore ..particularly a polyvinyLchloe Q C To? the;iresultinglldispersion is .70

ride,,polymerization product containing at least 40% by weight of combinedechlonine-iie. g polyn vinyl chloride," itself "Lorna vinyhchloiiideicopolyq mer comprising mainly; ,vinyl chloride; ion-instance a copalymenof byrweight Bolto ,99 ,of

vinyl chloride (in.1..:.th'e;copairmenmoleculeicand;- ZOto 1% of another monomeric material cone-i tai-ning a ,Cl-Ia:=- grQuping-l which 'is ircopolyimerizable c, therewith, for; instance a zvinylidene." chloridaea dower: alkyL- acrylate (er s, methyl.

ethyl, etc, :acrylates) ,,.',o;rl.a vinyl ester. of man aliphatichnonocarboxyliciacid-l esign vinyl acetate, vinylpropionate, etc.'), or other thermoplastic substance containing at least 20% by Weight-19f; combined halogen and capable of rupturing under heat atcarbon-halogen bonds. This mixture is thoroughly'agitated until a homogeneous liquid com-position or dispersion is obtained.

A more specific example of the preparation of such a dispersion of-the metallic "oxide and halogen-.containingnq'thermoplasticnsubstance is as follows: v

A small-iamountao-f:dispersing ragentflmore particularly' l3 parts-by weightofa sodium salt of a condensationmproduct ofeformaldehyde and a naphthalene sulfonicacid, is (dissolved: in 5'7"! parts 'by weight of water. Under rapid stirring with 1 a homogenizing-type of stirrer, 410 parts by weight of antimony trioxide is added to the solution. The resulting dispersion is then passed through a colloid mill to reduce the particle size to one micron or less. One hundredand thirtysix' '(136")fparts"offthe" antimony trioxide dispersion is addd -to an aqueous?dispersioncontaining 55 56 cy *-weight ri-f-an 'unplasticized vinyl*chlb ride'i copdlymer containing betiveenand by weight of vinyl chloride in the copo-lymer: The aqueous-wiispersior'r ofthe -vinyl' chlori'de copoly mer may beband preferably theproduct--which-* is iavailable from' the Bf F. Gdodr-ich-Che'mical- Company, nk ronw-Ohio; underthetrade name of fiGeon'-L-ate x X451 1 Thet'vinyl"chlci ide:copolymer used in the above aqueous dispersion :ands in:dispersionsreferredto iniotheiv examples whichrfollow; may begv-for ex amplam copolymereofgrbyilweightb about ;801% to I lowervalkyliacrylate, suchcior instancejas methy-L-J Whe-ni'the finely divided:antimonyatrioxideyor a other metallicr oxide-of athe? kindrusedrin practicing ourainventionais :1incorporated?iwithutheiwvaterer soluble oxygen-containing acid of phosphorus; and the water-.solublelnitrog-enous substance prior to i;he.;additi0n of theiammonium hydroidd'ilandil the :hal-ogen-containingrthermcplastic.substance;: this; maycbe dona i-forsinstance,mby addingitheii, metallicsoxidez-iin" tllBYiOI-nlzfifwfi: dispersiom'preez: pared v-asa hasejust'ibeem desctibe'd tto"thejrwaters containingi'the athercingredientsiz Or;:the: metala; licioxide and-a suitable dispersingnagentpe; g.,:a sodiumisalt/ of condensation prpductvofeformale't dehyde=and= a naphthaleneisulfonic acid-(may becaddedeto the; water lcontaining: thei-cthereingrediay; entsaaandsthe @metallic .oxideiz'dispersedi therein while the?iwater1solublescomponentsnr-e:dissolve r ingintthewatemzl i In order that thoseiskilledin ltherart. lbctterlmayr. understandithoivathe tpresen-t;v invention i be carried ;-.intos-eff=ect,-= .thezltollcwing QQXQIHLQ1S=IBIGW given-libyeway eof'iiilustratiomand.i-not-ubyz wayq-pfv limitatiorim Allcparts and percentages ware! bye eighties :Dispelsing agent, more particularly a sodium salt of a condensation product of formal- 8 the dilute dispersion being stable on standing at room temperature for a period of more than 24 hours. It had a pH of about 7.2.

dehyde and a naphthalene sulfonic acidfl 5 Example 3 Finely divided antimony trioxide 147 Urea v872 This example illustrates the results obtained Ammonium hydroxide (approx. 28% NH3)' 120 when the ammonium hydroxide containing ap- Aqueous dispersion containing 55-56% by proximately 28% NI-Is constitutes 4%, 6% and Weight of an unplasticized vinyl chloride 10' 9% by weight of the aqueous dispersion, and for copolymer containing between 80 and 95% purpose of comparison there are also given the by weight of vinyl chloride in the copolyresults when the same concentration of ammomer 236 nium hydroxide constitutes 3% by Weight of the Water 157 dispersion.

Amount of NH4OH in the dispersion 3% Parts Parts Parts Parts Urea 1, 624. 1, 624. 50 l, 083. 0 1, 624. 50 Monoguanidine phosphate. -4 813.00 813.00 542. O 813. 00 Dispersing agent, more particularly a sodium salt of a 8. 85 8. 85 5.9 8.84

condensation product of formaldehyde and a naphthalene sulfonic acid. 5 Finely divided antimony trioxide 271. 50 271. 50 181. 0 271. 50 Aqueous dispersion containing -56% by weight of an 475. 50 475. 50 317.0 475. 50 implasticized vinyl chloride copolymer as in Example Ammonium hydroxide (approx. 28% NH 112. 50 150.00 150. 0 337.50 ator 444. 00 406. 50 221. 0 219v 00 pH of dispersion 6. 4 6. 6 7.0 8. 1 Character of dispersion Unstable, rela- Stable, no sepa- Stable, very vis- Stable, thick tively thin, ration of clear cous, no sepapaste, no sepaclear liquid liquid on ration of clear ration of clear separated on standing for liquid on liquid on standstanding for 24 more than 1 standing for ing for more hours. week. more than 6 than 6 months.

months.

The water was added first to a mixing tank provided with means for heating, cooling and stirring the contents, and the remaining materrials were added in the order listed. The monoguanidine phosphate, dispersing agent and antimony trioxide were added to the water, and stirring and heating of the mixture were begun. The urea was slowly fed into the mixture so thatthe endothermic reaction held'the temperature constant. Heating was continued until the salts had completely dissolved, the mixture being brought to a temperature of about 180-190 F. Cooling was then started (by discontinuing the introduction of steam into the jacket of the tank), and at 170 F. the ammonium hydroxide was added. This caused the temperature to drop to about 160 F. When the temperature had reached 155 F. the aqueous dispersion containing the vinyl chloride copolymer was slowly added, the contents of the mixing tank then being warmed so that its temperature would not fall below about 150 F.

The hot dispersion was passed through a preheated conduit into the first of two Votators (made by The Girdler Corporation. Louisville, Kentucky). The jacket of the first half of the first Votator was heated slightly in order to avoid too rapid crystallization at the inlet with the possibility ofplugging the inlet line. The second half of the first Votator and the entire second Votator were cold jacketed, and the water flow was manually adjusted so that the thoroughly agitated and rapidly cooled dispersion being discharged from the Votator was at a temperature of about 80-85 F. (A Votator is'a specific type of apparatus in which the dispersion can be vigorously agitated with rapid cooling.)

The finished, homogeneous dispersion con tained about 81.8% by Weight of solids. It was a stable dispersion having a storage stability at room temperature of more than five months. It was dilutable with water to 55% solids content,

Each of the above dispersions was prepared by heating'to about 180 E1, while stirring vigorously, a mixture containing all of the aforementioned ingredientswith the exception of the aqueous dispersion (Geon Latex X415) containing the vinyl chloride copolymer. The resulting dispersion was cooled to about 156 11, at which temperature the dispersion of the vinyl chloride copolymer was added. The mixture was vigorously agitated while rapidly cooling the same to a temperature of about 50 to 60 F.

Exampie 3- This example illustrates the results obtained when the ammonium hydroxide is employed in an amount corresponding to about 6 to 6.3%, by weight of the dispersion, of ammonium hydroxicle containing approximately 2.8 NHs, and the amount of solids in the dispersion is about to by weight thereof.

Approx. amount of NEiOH 6% 0. 3%

in. the dispersion.

Approx. amount of solids in 80% 85% the dispersion.

Pa ts Parts Urea. 8G. 80 86. 80

Monoguanid ephosphate'... 43. 20 43.20

Dispersing agent, more parti- 0.48 0.48

cularly a sodium salt of a condensation product of formaldehyde and a naphthalene sulfonic acid. I

Finely divided antimony tri- 14. 40 14. 40

oxide.

Aqueous dispersion contaiu- 25. 50 25. 50

ing 55-56% by Weight of an unplasticized vinyl chloride copolymer 'as in Examples 1 and 2.

Ammonium hydroxide 12.00 12.00

(approx. 28% NHZ).

Water 17.00 7.00

Character of dispersion Stable, very Stable, thick viscous, no paste, no sep ion of clear liquid on standing for more than 6 months,

The aqueous dispersions of our invention are useful in the production of a wide variety of flame-resistant cellulosic materials, e. g., wear ing apparel of all kinds, especially childrens clothes'and clothing used by the armed forces, curtains, draperies, sheeting, furniture cover-- ings, linings for electric blankets, net fabrics, non-woven fabrics, chenilles, etc., and which are made of cellulosic materials such as are described in the first paragraph of this specification and elsewhere herein. In some cases the concentrated dispersions as initially produced may be applied to the textile by knife-coating processes; but preferably the concentrated dispersion is diluted with a suitable amount of water so as to obtain a dilute dispersion with which the textile readily may be impregnated, e. g., by immersion inthe dispersion, as is described more fully (including all of the steps of the treating process) in the aforementioned copending Loukomsky et a1. application Serial No. 64,416 filed concurrently herewith.

We claim:

f 1. In a method of preparing an aqueous dis;

per-sion which is adapted for use in imparting flame-resisting characteristics to cotton cloth and other fibrous cellulosic materials of the class consisting of natural and regenerated celluloses and mixtures thereof, said dispersion comprising, by weight, from about to about 35% of water, and ingredients comprising (1) a finely divided, oxygen-containing substance of the group consisting of tin, titanium, antimony and bismuth oxides and mixtures thereof and (2) a thermoplastic substance containing at least by weight of combined halogen and capable of rupturing under heat at carbon-halogen bonds,

the ingredients of (1) and (2), which together are designated hereinafter as (A), being employed in a weight ratio of 1 part of the former to from 0.6 to 20 parts of the latter and being dispersed in water containing ingredients initially in the form of (3) a water-soluble salt of an oxygen-containing acid of phosphorus wherein the phosphorus atom has a valence of 5 and (4) a water-soluble nitrogenous substance of the group consisting of urea, biuret, ammonium cyanate, ammonium dicyanimide and mixtures thereof, the ingredients of (3) and (4), which together are designated hereinafter as (B), being employed in a weight ratio of 1 part of the former calculated as H3PO4 to from 1 to 20 parts of the latter, and the ingredients of (A) and (B) being employed in a weight ratio of 1 part of the former to from 0.2 to 8 parts of the latter, the improvement which consists in incorporating into'the said dispersion ammonium hydroxide in an amount corresponding to not less than about 4%, by weight of the said dispersion, of ammonium hydroxide containing approximately 28% NH3.

2. In a method of preparing an aqueous dispersion which is adapted for use in imparting flame-resisting characteristics to cotton cloth and other fibrous ceilulosic materials of the class consisting of natural and regenerated celluloses and mixtures thereof, said dispersion comprising, by weight,'from 15 to of water, and ingredients comprising (1) a finely divided oxide of antimony and (2) a thermoplastic vinyl resin containin at least 40% by weight of combined chlorine, the ingredients of (1) and (2), which together are designated hereinafter as (A), being employed in a weight ratio of 1 part of the former to from 0.6 to 20 parts of the latter and being dispersed in water containing ingredients initially in the form of (3) a water-soluble guanidine phosphate and (4) urea, the ingradients of (3) and (4), which together are designated hereinafter as (B), being employed in a weight ratio of 1 part of the former calculated as H3PO4 to from 1 to 29 parts of the latter, and the ingredients of (A) and (B) being employed in a weight ratio of 1 part of the former to from 0.2 to 8 parts of the latter, the improvement which consists in incorporating into the said dispersion, during its preparation, ammonium hydroxide in an amount corresponding to from 4 to 9%, by weight of the said dispersion, of ammonium hydroxide containing approximately 28% N H3.

3. The method of preparing a relatively stable aqueous dispersion which is adapted for use in imparting flame-resisting characteristics to cotton cloth and other fibrous cellulosic materials of the class consisting of natural and regenerated celluloses and mixtures thereof, said method comprising dissolving in water with the aid of heat (1) a water-soluble salt of an oxygen-containing acid of phosphorus wherein thephosphorus .atom has a valence of 5 and (2) a water-soluble nitrogenous substance of the group consisting of urea, biuret, ammonium cyanate, ammonium dicyanirnide and mixtures thereof, the ingredients of (1) and (2) which together are designated hereinafter as (B), being employed in a weight ratio of 1 part of the former calculated as H3PO4 to from 1 to 20 parts of the latter, and the amount of water employed being such as will yield an approximately saturated solution, at a temperature of about F. to about F., of the said in gredients of 1) and (2) adding to the resulting solution, at an elevated temperature not higher than about F., ammonium hydroxide in an amount corresponding to from 4% to about 9%, by weight of the final aqueous dispersion containing all of the ingredients, of ammonium hydroxide containing approximately 28% NI-Ig; mixing with the solution to which the ammonium hydroxide has been added and dispersing therein an aqueous dispersion containing (3) a finely divided, oxygen-containing substance of the group consisting of tin, titanium, antimony and bismuth oxides and mixtures thereof and (4) a thermoplastic substance containing at least 20% by weight of combined halogen and capable of rupturing under heat at carbon-halogen bonds, the ingredients of (3) and (4), which together are designated hereinafter as (A), being employed in a weight ratio of 1 part of the former to from 0.6 to 20 parts of the latter, the ingredients of (A) and (B) being employed in a weight ratio of 1 part of the former to from 9.2 to 8 parts of the latter and the dispersion, after adding the dispersion comprising the ingredients of (3) and (4), comprising, by weight, from about 15% to about 35% of water; and agitating the resulting dispersion while rapidly cooling the same thereby to obtain 'an aqueous dispersion which is stable against separation of solids for a prolonged period at room temperature.

4. A method as in claim 3 wherein the watersoluble salt of (1) is a water-soluble guanidine phosphate, the watersoluble nitrogenous substance of (2) is urea, the finely divided oxygencontaining substance of (3) is antimony trioxide and the thermoplastic substance of (4) is a vinyl chloride polymerization product containing at least 40% by weight of combined chlorine.

5.; The method of preparing a relatively stable aquepus dispersion which is adapted for use in trues iii-.til tllbt.

..imparting fiame resisting characteristics to cotton cloth and -other fibrous cellulosic-materials of the. class consisting of: naturaL and regenerated celluloses and mixtures thereof-, saidmethod comprising dispersingin water with the aid of heat 'cy anate, am-monium dicyanimide and mixtures thereof and (3)" a finely divided; =oxygen-containing substance-oi the group'consisting o'f tin,

titanium-,antimony andbismuth oxides and mixtures"thereof; -the ingredientsf (l) and (2),

' which together-=are designated hereinafter (B) ,being employed in a' weight'ratio of l part-of the-former calculated as H3PO4 to from 1 mac parts of the latter, and the amount of wateremployed being'such as will yield an approximately saturated solution; at temperature of ab'out 140 F. to about 'l6() F-.,'- of the-saidingredients of (1)--ar1d (2); addingto -theresulting dispersion, at an elevatedtemperaturenothigher than about-180 F., ammonium hydroxide in an amountcorresponding to from 4% to about 9%, by' weight of the final'aqueous dispersion containing all of the ingredients; I of ammonium-hydroxide containing approximately 28%' '-N-H3;

mixing with the-'-dispersion-towhich the amnionium' hydroxide has been added-and dispersing therein an aqueous dispersion comprising (4) a thermoplastic"substancecontaining at least 26% by weight of combined halogen and capable of rupturing under heat 'at carbon-halogen "bonds, the ingredients of I (3 and (4), which-together are-designated hereinafter asbt A), being employed in a weight ratio of l part oi the iormerto from 0.6 to"- 20:- parts of the latter, the ingredients of (Po-and (B) being employed in a weight ratioof 1 part of the former to from 0.2 to 8 parts oi-the-latter and 'the-dispersion, after padding-the dispersion-containing vthe thermoplastic substance of (4), comprising; bycweight, from about. 15%,tos about. 35% of water; and

agitating 'the'resulting dispersion while rapidly cooling the same thereby-to. obtain angaqueous dispersion which. isv stable for aiprolonged period at rooin'temperature. is

6. A method as in claim ii wherein th watersoluble salt of (1) is a water-soluble guanidine phosphate, the water-soluble nitrogenous substance of (2) is urea, the finely divided oxygencontaining substance of (3) is antimony trioxide and the thermoplastic substance of (4) is a vinyl chloride polymerization product containing at least 40% by Weight of combined chlorine.

7. The method of preparing a relatively stable aqueous dispersion which is adapted for use in imparting flame-resisting characteristics to cotton cloth and other fibrous cellulosic materials of the class consisting of natural and regenerated celluloses and mixtures thereof, said method comprising dissolving in water with the aid of heat (1) monoguanidine phosphate and (2) urea, the

ingredients of (1) and (2), which together are designated hereinafter as (B) being employed in a weight ratio of 1 part of the former calculated as HaPOi to form 2 to 6 parts of the latter, and th amount of water employed being such as will yield an approximately saturated solution, at a temperature of about 150 F., of the said ingredients of (1) and (2) adding to the resulting solution, at a temperature between about 160 F. and about 180 F., ammonium hydroxide in an -amount correspondingsto not "les's' than i 7a and not -more than 'about 9 by' weighti'or the' final aqueous dispersio-m. containinglall -Iof izthei" ingredients, of ammoniumhydroxide containingvaapproximatelyli 28 Nl-Isg addingcto the solution'ato t which the ammonium-hydroxide bas -been :added "and F dispersing 'therin anaqueous dispersion containing (3)1 finely divided: "antimonyftrioxide and (4) a vinyl 'chloride ipolymerization'zprb'duct 1 o containing atmleastaril) %:b-y vweighti of: combined fr chl orine', the ingredients "of :t (3 )zrrand (4 )3: which together: are designated.ihereinafter "Iat4i(A) Ibeing employed in a weight ratio iof impart of the formertofrom; 0.8 :to 4 parts o'ftthe'zlatter; the 1 ingredients I oi my and (B)-:beingr:employed:in a weightratio of 1 part ofthe'. former to from onto 3 -p'artsof the latter-rand theadispersiong after sadd- -ing the; dispersion zcomprisinga:the iIIEIQdiGIItS-E'Of 3) and: (4)", containingafrom toi25 %:ibyi-weig?ht ot :water; and agitatingi the. resultingtdi-SperS'ion "while rapidly cdolingfithe samet-to altemp between .abou-t' 509" Fi andisabouts90? rthere'by 2 to obtain an aqueousi dispersion'which;whenzdi- 1 -l-utedwith-water to'ziyilda dispersion icontaining 2 pproximatelyr50 %xby. .weighttofholids; 'showsmo nseparationrof solidsmponstandingundisturbedat room temperature-don a% period JOfitatfileaSt-5-24 hours. e I I b'i 'The; method ofip'reparing aarelatively stable 39 aqueous dispersion which isiia'daptedcfonauserin imparting.fiflame resisting oharacteristicsrto cotton -cl 0th: and other fibrous "(3811111051021- materials ofothe' class c'ons'istingi of naturaland: regenerated c'elluloses and? mixtures .ithelteofgpnsaidt method *comprising dispersing;inaiwater rwithz the aid:- of 1 heat iingr'e'dients-:icomprising 61) ;monog-uanidine phosphate, (2) urea and (3')zffinelyadividedzanti- I mony r. triox ide', 1' ithe lingredients-zof (1 Land L (2) which-together are designatedxhereinafter'ase(B) being employeddn a weight-tratiobf :1 part-.ofithe former calculatedat JI-IsPO4 torfrom 2: to G-iparts --of the latter; andwthe amount ofzwaterr employed I being I such-as willzyieldi gntrapproximatelyrsaturatedsolutiong at a temperatureofr about-1,150 01 the said ingredientst-of (1): -andz':(2):;a'a-ddin"glto the resulting-dispersion, at atemperat ehetween about 160 F. {1 and about1180fZFJI ammonium hydroxide in an amount correspondingcto; not less than '4 :and notmorathan: about".9 %;,-..-;by weight of the final aqueous dispersion containing all of the ingredients, of ammonium hydroxide containing approximately 28% NH:;; adding to the dispersion to which the ammonium hydroxide has been added and dispersing therein an aqueous dispersion containing (4) a vinyl chloride polymerization product containing at least 40% by weight of combined chlorine, the ingredients of (3) and (4), which together are designated hereinafter as (A), being employed in a weight ratio of 1 part of the former to from 0.8 to 4 parts of the latter, the ingredients of (A) and (B) being employed in a weight ratio of 1 part of the former to from 1 to 3 parts of the latter and the dispersion, after adding the dispersion containing the vinyl chloride polymerization product of (4), containing from 15 to 25% b weight of water; and agitating the resulting dispersion while rapidly cooling the same thereby to obtain an aqueous dispersion which, when diluted with water to yield a dispersion containing approximately by weight of solids, shows no separation of solids upon standing undisturbed at room temperature for a period of at least 24 hours. 9. An aqueous dispersion which is adapted for use in imparting flame resisting characteristics tocotton cloth and other fibrous cellulosic materials of the class consisting of natural and regenerated celluloses and mixtures thereof, said dispersion comprising water and ingredients comprising (1) a finely divided, oxygen-containing substance of the group consisting of tin, titanium, antimony and bismuth oxides and mixtures thereof and (2) a thermoplastic substance containing at least by weight of combined halogen and capable of rupturing under heat at carbon-halogen bonds, the ingredients of 1) and (2), which together are designated hereinafter as (A), being employed in a weight ratio of 1 part of the former to form 0.6 to 20 parts of the latter and being dispersed in water containing ingredients initially in the form of (3) a water-soluble salt of an oxygen-containing acid of phosphorus wherein the phosphorus atom has a valence of 5 and (4) a water-soluble nitrogenous substance of the group consisting of urea, biuret, ammonium cyanate, ammonium dicyanimide and mixtures thereof, th ingredients of 3) and (4), which together are designated hereinafter as (B), being employed in a weight ratio of 1 part of the former calculated as I-I3P04 to from 1 to 20 parts of the latter, and the ingredients of (A) and (B) being employed in a weight ratio of, 1 part of the former to from 0.2 to 8 parts of the latter, said dispersion also containing ammonium hydroxide in an amount corresponding to not less than about 4% by weight thereof of ammonium hydroxide containing approximately 28% NHs, the total amount of Water which is present in the said dispersion, including that which is present in combination with ammonia in the form of ammonium hydroxide, being from about 15% to about by weight of the dispersion.

10. An aqueous dispersion which is adapted for use in imparting flame-resisting characteristics to cotton cloth and other fibrous cellulosic materials of the class consisting of natural and regenerated celluloses and mixtures thereof, said dispersion comprising water and ingredients comprising (1) finely divided antimony trioxide and (2) avinyl chloride polymerization product containing at least by weight of combined chlorine, the ingredients of (1) and (2), which together are designated hereinafter as (A), being employed in a weight ratio of 1 part of the former to from 0.8 to 4 parts of the latter and being dispersed in water containing ingredients initially in the form of (3) monoguanidine phosphate and (4) urea, the ingredients of (3) and (4), which together are designated hereinafter as (B), being employed in a weight ratio of 1 part of the former calculated as H3PO4 to from 2 to 6 parts of the latter, and the ingredients of (A) and (B) being employed in a weight ratio of 1 part of the former to from 1 to 3 parts of the latter, said dispersion also containing ammonium hydroxide in an amount corresponding to not less than 4% and not more than about 9% by weight thereof, the total amount of water which is present in the said dispersion, including that which is present in combination with ammonia in the form of ammonium hydroxide, being from 15% to 25% by weight of the dispersion, and the said dispersion being dilutable with Water to yield a dilute aqueous dispersion containing approximately by weight of solids, which dilute dispersion shows no separation of solids upon standing undisturbed at room temperature for a period of at least 24 hours.

11. An aqueous dispersion as in claim 10 wherein the dispersion contains ammonium hydroxide in an amount corresponding to approximately 6% by Weight thereof of ammonium hydroxide containing approximately 28% NH3, and the total amount of water which is present in the dispersion, including that which is present in combination with ammonia in the form of ammonium hydroxide, is approximately 20% by weight of the dispersion.

12,! A method as in claim 1 wherein the ammonium hydroxide is incorporated into the defined dispersion during the preparation of the latter.

MAURICE R. BURNELL. WILLIAM J. VAN LOO, JR.

REFERENCES CITED Zfhe following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,357,725 Bennett Sept. 5, 1944 2,413,163 Bacon Dec. 24, 1946 sol 

9. AN AQUEOUS DISPERSION WHICH IS ADAPTED FOR USE IN IMPARTING FLAME-RESISTING CHARACTERISTICS TO COTTON CLOTH AND OTHER FIBROUS CELLULOSIC MATERIALS OF THE CLASS CONSISTING OF NATURAL AND REGENERATED CELLULOSES AND MIXTUES THEREOF, SAID DISPERSION COMPRISING WATER AND INGREDIENTS COMPRISING (1) A FINELY DIVIDED, OXYGEN-CONTAINING SUBSTANCE OF THE GROUP CONSISTING OF TIN, TITANIUM, ANTIMONY AND BISMUTH OXIDES AND MIXTURES THEREOF AND (2) A THERMOPLASTIC SUBSTANCE CONTAINING AT LEAST 20% BY WEIGHT OF COMBINED HALOGEN AND CAPABLE OF RUPTURING UNDER HEAT AT CARBON-HALOGEN BONDS, THE INGREDIENTS OF (1) AND (2), WHICH TOGETHER ARE DESIGNATED HEREINAFTER AS (A), BEING EMPLOYED IN A WEIGHT RATIO OF 1 PART OF THE FORMER TO FORM 0.6 TO 20 PARTS OF THE LATTER AND BEING DISPERSED IN WATER CONTAINING INGREDIENTS INITIALLY IN THE FORM OF (3) A WATER-SOLUBLE SALT OF OXYGEN-CONTAINING ACID OF PHOSPHORUS WHEREIN THE PHOSPHORUS ATOM HAS A VALENCE OF 5 AND (4) A WATER-SOLUBLE NITROGENUS SUBSTANCE OF THE GRUP CONSISTING OF UREA, BIURET, AMMONIUM CYANATE, AMMONIUM DICYANIMIDE AND MIXTURES THEREOF, THE INGREDIENTS OF (3) AND (4), WHICH TOGETHER ARE DESIGNATED HREINAFTER AS (B), BEING EMPLOYED IN A WEIGHT RATIO OF 1 PART OF THE FORMER CALCULATED AS H3PO4 TO FROM 1 TO 20 PARTS OF THE LATTER, AND THE INGREDIENTS OF (A) AND (B) BEING EMPLOYED IN A WEIGHT RATIO OF 1 PART OF THE FORMER TO FROM 0.2 TO 8 PARTS OF THE LATTER, SAID DISPERSION ALSO CONTAINING AMMONIUM HYDROXIDE IN AN AMOUNT CORRESPONDING TO NOT LESS THAN ABOUT 4% BY WEIGHT THEREOF OF AMMONIUM HYDROXIDE CONTAINING APPROXIMATELY 28% NH3, THE TOTAL AMOUNT OF WATER WHICH IS PRESENT IN THE SAID DISPERSION, INCLUDING THAT WHICH IS PRESENT IN COMBINATION WITH AMMONIA IN THE FORM OF AMMONIUM HYDROXIDE, BEING FROM ABOUT 15% TO ABOUT 35% BY WEIGHT OF THE DISPERSION. 